Eye Color & Genetics

Ever wonder why your eyes are blue, green, brown, or somewhere in between? The colored part of your eye, the Iris, contains pigmentation which determines our eye color. The mix of pigmentation in your Iris is created through the unique combination of chromosomes that are given to you by your parents.

How eye color develops

Eye color is not as simple as other genetic traits with three different genes contributing to your eye color. Due to dominant gene types, darker colors like brown overpower lighter colors like blue and green. Colors such as gray, hazel, and multiple combinations are not as common and are not yet completely understood.

Most babies are born with blue eyes, but did you know their eyes can darken for three years? Melanin is a pigment not present at birth, which develops with age and causes eyes to darken. The more melanin someone has, the darker their eyes will be.

Facts About Common Eye Colors:

Blue: People with blue eyes have less melanin in their eyes than any other color. Blue eyes are thought to come from a genetic mutation of one individual.

Green: This is voted the most attractive and one of the rarest eye colors.

Hazel: The hue of hazel eyes changes based on what you are wearing and the type of lighting you are in. The colors brown, green, amber, and blue can be seen in hazel eyes.

Changes in eye color

When your pupil changes size, the pigments in the iris of your eye compress or spread apart causing the color of your eyes to change. Your pupils change size for a variety of reasons including changes in light and the distance of the object you are focusing on. Emotions can also change the pupil size and iris color.

Heterochromia

Heterochromia is a condition in which a person’s eyes are different colors, caused by one eye having more melanin than the other. Heterochromia is usually present at birth and is not considered an eye disease as it commonly does not cause vision problems.